 
 (defn draw-pixel [image data x y r g b & a]
   (println "draw-pixel" x y r g b (first a))
-  (let [offset (+ (* x 4) (* y (.-height image) 4))]
+  (let [offset (+ (* x 4) (* y (.-width image) 4))]
     (aset data offset r)
     (aset data (+ offset 1) g)
     (aset data (+ offset 2) b)

        image (.createImageData ctx canvas-width canvas-height)
        data (.-data image)]
    ;(draw-pixel image data 0 0 0 0 0) ;test
    ;(draw-pixel-color image data 20 20 [255 0 0]) ;test
    (draw-line image data 30 30 200 200 [0 0 0])
    (.putImageData ctx image 0 0)))
  

        (draw-pixel-color image data y x color)
        (draw-pixel-color image data x y color))
      (let [error (- error dy)]
        ;(println "error" error)
        (if (< error 0)
          (recur image data x1 y1 x2 y2 dx dy (+ error dx) (+ x 1) (+ y ystep) ystep color steep)
              (recur image data x1 y1 x2 y2 dx dy error (+ x 1) y ystep color steep))))))
